The aura of effect refers to a certain influence a persons presence has on those around him or her, due to the infectiousness of their personality. Meaning that whenever you spend time with the person, their aura of effect rubs off on you and their personality characteristics replicate in you, mainly in a positive way.

Person one: Man, Dom is such an awesome guy. He's so happy, upbeat, friendly, eccentric and nice that he makes me want to have fun, be eccentric and happy. He's the kind of guy that makes me a better person. How come?
Person two: Yeah, it's the aura of effect that he has-you start to become like him when you hang around him.
Person one: Sweet.
Person two: I'd tap that.